Malleable penile prosthesis: penoscrotal approach

Operative visualisation

UrOops3D · UroRef · © Nity G

How to use this module. Play through the nine steps, or use Back and Next. Watch the track along the lateral wall, the two readings on the panel, the rod folded in and straightened, and the final bend down and up. Try a trigger to see a wrong track and its correction.

Operative steps

1. Choose the device: one component A man in his sixties with erectile dysfunction after failed medical therapy has chosen a malleable device because his hands cannot work a pump; the guideline names limited dexterity as one reason to choose a semi-rigid device. He has been told that the penis stays firm at all times, that it is bent down to conceal and up to use, and that concealment is poorer than with an inflatable device. The alternatives were named: a two- or three-piece inflatable device, the infrapubic or subcoronal routes to the same corpora, and, in a different man, immediate malleable insertion after refractory ischaemic priapism. Nothing here is reversible.
2. Penoscrotal exposure Supine, prepped and draped, a urethral catheter in so the urethra is felt throughout. A vertical incision on the median raphe at the penoscrotal junction, carried through the dartos and the superficial layer of Buck's fascia, and a self-retaining retractor set. The corpus spongiosum is retracted to one side and the corpus cavernosum of the first side identified; the deep layer of Buck's fascia comes off it to expose the tunica albuginea.
   where it bites: the spongiosum and urethra are ventral and in the midline; the tunica to be opened is lateral to them, never under them.
3. Corporotomy Two absorbable stay sutures are placed laterally in the tunica and a corporotomy made between them. The stays hold the edges up, keep the opening where it was planned and will be tied over the rod at the end. Cavernosal tissue shows in the opening.
   where it bites: a corporotomy that wanders ventrally brings the spongiosum into the field and the urethra under the dilator.
4. Dilate proximally: the lateral wall Dissecting scissors with the tips pointed laterally tunnel the corpus toward the ischial tuberosity, then dilators of rising size follow along the lateral corporal wall until the crus is reached. The feel is the feedback: a smooth glide is the channel, a sudden give is a perforation. Saline with antibiotic is irrigated into the corpus.
   where it bites: the septum is medial and thin; a dilator that drifts medially crosses into the other corpus. A dilator that drives on past the crus perforates it.
5. Dilate distally: the ventral urethra The same scissors and dilators pass distally along the lateral wall to the mid-glans. The hand on the catheter feels where the urethra is. The glans is supported so the distal dome is not driven through.
   where it bites: ventral drift puts the dilator through the thin ventral tunica into the urethra; over-eager distal passage perforates the dome.
6. Measure both sides With the penis on stretch the measuring and insertion tool is passed proximally and then distally and the length of each read at the corporotomy; the sum is the corporal length. The second corpus is exposed, opened, dilated and measured in the same way. The two sums are compared before any rod is chosen.
   where it bites: a side-to-side mismatch means a wrong track on one side, not a difference in the man; it is investigated, not averaged.
7. Size and trim Rod diameter is chosen from the dilated channel and rod length from the two readings; the rods are soaked in antibiotic solution. The end is trimmed to the measured length and a rear tip extender added to each rod so the proximal end seats in the crus.
   where it bites: a rod too short leaves the glans unsupported and drooping; one too long pistons against the dome and erodes.
8. Place the rods With the penis on stretch the rod is positioned distally to the mid-glans, then partially folded on itself so the proximal end can be placed in the ipsilateral crus; it straightens and lies along the whole corpus with the distal tip under the mid-glans. The second rod goes in the same way and its position is confirmed. Nothing is forced.
   where it bites: a rod that will not lie straight is telling the surgeon the track or the length is wrong; forcing it perforates.
9. Close and position The stay sutures are tied over the rod to close each corporotomy watertight, the needle kept clear of the rod. The wound is irrigated, haemostasis secured and the retractor removed. Dartos is closed with a running absorbable suture and the skin with a subcuticular stitch; the penis is dressed and taped to the abdomen to limit swelling, with the catheter on free drainage. Before he leaves he is shown the bend down and the bend up.
   where it bites: a needle through the rod at closure damages the device that was just placed.

Complications and immediate saves

Trigger each of these live in the Animation tab, then read the save: the first move, the escalation trigger, and the line that goes in the op note.

FRCS viva questions

The examiner stems this scene prepares you for. Try to answer out loud first, then reveal, and learn the discriminator, the detail that turns a pass into a strong pass.

Evidence and guidance

Curriculum. Supports learning relevant to the ISCP Urology Curriculum syllabus topic Erectile dysfunction and penile prosthesis surgery. Not a workplace-based assessment and not evidence of competence.